000
FXUS63 KOAX 041736
AFDOAX
Area Forecast Discussion
National Weather Service Omaha/Valley NE
1136 AM CST Sun Dec 4 2016
.SHORT TERM...(today through Tuesday)
Issued at 255 AM CST Sun Dec 4 2016
A very narrow 30-40 mile wide of 2-4" along I80 occurred yesterday
evening, which was higher than our original forecast. This was a
result of not having enough QPF in the original forecast, by as
much as 0.2 to 0.3 of water equivalent. Also, there wasn`t as
much of a changeover/mix with rain as previously thought, and the
mesoscale band allowed snowfall rates to overwhelm the melting
that was occuring. What remains of the precipitation is winding
down early early this morning, having ending west of a line from
Beatrice to Plattsmouth to Harlan, IA. The remaining rain/snow
mix will continue to push east and out of the area by 6-7 am.
Sunday and Monday will actually be somewhat mild, with highs in
the 40s, well above normal. Did account for a slightly cooler
swath where the snow exists, but it should melt through the day.
A cold front will arrive in the area Monday afternoon, then sweep
across the area Monday night. This will usher in sharply colder
air. While there may be a small chance of rain or snow in
northeast Nebraska Monday evening, couldn`t discount a few
flurries as the colder air rushes in Monday night as well, but
that`s not currently in the forecast.
Highs Tuesday will be below normal in the upper 20s to mid 30s,
but conditions should be dry.
.LONG TERM...(Tuesday night through Saturday)
Issued at 255 AM CST Sun Dec 4 2016
The midweek weather system continues to be the primary concern as
models struggle to come to a consensus. The operational GFS and
Canadian models are taking a more southern route, which would just
graze the KS/NE border with snow chances. The ECMWF, SREF, and GFSEnsemble remain a bit further north with higher snow chances and
amounts over a larger portion of our forecast area. Still have
snow chances in the grids, but may have to continue to tweak in
the next day or two as models hone in the details. The bigger
story will continue to be the sharply colder temps with highs in
the teens and 20s Wednesday through Friday, and could be a little
colder if we do get some snow. Temps do moderate a little by
Saturday into the 20s to lower 30s, but the models also suggest a
better chance of snow that day, now in the 40-60% range.
&&
.AVIATION...

-- Changed Discussion --

(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 1128 AM CST Sun Dec 4 2016
IFRstratus deck continues to every so slowly work southeast
across the area, and the edge is very near the KOMA/KLNK
terminals. We will likely see this deck in there for a couple more
hours this afternoon before VFR conditions set in. The only other
concern is how far the clouds move to the east tonight as
southeast winds develop. We will keep them out of KOMA for now,
but it may be close overnight. We may also see some fog develop
on the western edge of the stratus deck overnight, which could
affect the KOMA TAF tonight, but confidence is to low to include
currently.